Sara Morris, age 8, of Lethbridge, Alberta, Canada, for her question:

How big is a baby polar bear?

Papa Polar Bear is eight feet long and weighs almost half a ton. Mama Polar Bear is somewhat shorter. But she weighs a whopping 700 pounds    which is about as much as five or six human mothers. You would expect such huge parents to have big bouncing babies. But this is not so. A newborn human baby weighs about as much as five newborn polar bear cubs.

The mother polar bear gives birth to one or two, three or four cubs in the middle of the winter. Each baby bear is about one foot long and weighs one and a half pounds. Their first fur coats are rather thin and scraggly. So up there in the frozen north they stay very close to their big warm mother. The cubs open their eyes after about 33 days but they don't hear very well for the first couple of months. They stay with their mother until they are about ten months old. Then they are big enough and smart enough to go off on their own.